Shanghai International Circuit facelift extension 0.91

This is an extension for china_2021 track. The track is not included, since it is against RaceDepartment's policy - you do have to look/ask around to find it. Once you found it - simply copy over the content of the folder.

Changes:
- crowds! Simple and fps-friendly 2d crowds on all those massive stands, ready to cheer F1 and WEC events alike. Some are even waving animated flags!
- symmetrical trees in the original track were annoying me - had to chop all those and plant new trees, in a carbon-friendly way
- grass and kerbs were reshaded to add wear&tear for more immersion
- some material tweaks





I was planning to spend more time on this track, but since I haven't actually touched it for two months now - I want to release as-is, in case someone might enjoy it. I am quite satisfied with the added immersion and have switched to other tracks since, but more tweaks could be definitely added (e.g. displays, more trees, more flags and banners).

My extension wouldn't be possible without all the amazing work done by multiple very talented individuals!
If you want to re-use any of the (original) textures, models or shader settings from this extension - I have no objections whatsoever.
Comments and feedback are welcome, as well as suggestions for the next track to facelift!